1 files changed, 58 insertions, 53 deletions

diff --git a/drivers/fpga/fpga-bridge.c b/drivers/fpga/fpga-bridge.c
index a6c25dee9cc1..8ef395b49bf8 100644
--- a/drivers/fpga/fpga-bridge.c
+++ b/drivers/fpga/fpga-bridge.c
@@ -14,7 +14,7 @@
 #include <linux/spinlock.h>
 
 static DEFINE_IDA(fpga_bridge_ida);
-static struct class *fpga_bridge_class;
+static const struct class fpga_bridge_class;
 
 /* Lock for adding/removing bridges to linked lists*/
 static DEFINE_SPINLOCK(bridge_list_lock);
@@ -30,7 +30,7 @@ int fpga_bridge_enable(struct fpga_bridge *bridge)
 {
 	dev_dbg(&bridge->dev, "enable\n");
 
-	if (bridge->br_ops && bridge->br_ops->enable_set)
+	if (bridge->br_ops->enable_set)
 		return bridge->br_ops->enable_set(bridge, 1);
 
 	return 0;
@@ -48,62 +48,61 @@ int fpga_bridge_disable(struct fpga_bridge *bridge)
 {
 	dev_dbg(&bridge->dev, "disable\n");
 
-	if (bridge->br_ops && bridge->br_ops->enable_set)
+	if (bridge->br_ops->enable_set)
 		return bridge->br_ops->enable_set(bridge, 0);
 
 	return 0;
 }
 EXPORT_SYMBOL_GPL(fpga_bridge_disable);
 
-static struct fpga_bridge *__fpga_bridge_get(struct device *dev,
+static struct fpga_bridge *__fpga_bridge_get(struct device *bridge_dev,
 					     struct fpga_image_info *info)
 {
 	struct fpga_bridge *bridge;
-	int ret = -ENODEV;
 
-	bridge = to_fpga_bridge(dev);
+	bridge = to_fpga_bridge(bridge_dev);
 
 	bridge->info = info;
 
-	if (!mutex_trylock(&bridge->mutex)) {
-		ret = -EBUSY;
-		goto err_dev;
-	}
+	if (!mutex_trylock(&bridge->mutex))
+		return ERR_PTR(-EBUSY);
 
-	if (!try_module_get(dev->parent->driver->owner))
-		goto err_ll_mod;
+	if (!try_module_get(bridge->br_ops_owner)) {
+		mutex_unlock(&bridge->mutex);
+		return ERR_PTR(-ENODEV);
+	}
 
 	dev_dbg(&bridge->dev, "get\n");
 
 	return bridge;
-
-err_ll_mod:
-	mutex_unlock(&bridge->mutex);
-err_dev:
-	put_device(dev);
-	return ERR_PTR(ret);
 }
 
 /**
  * of_fpga_bridge_get - get an exclusive reference to an fpga bridge
  *
- * @np: node pointer of an FPGA bridge
- * @info: fpga image specific information
+ * @np: node pointer of an FPGA bridge.
+ * @info: fpga image specific information.
  *
- * Return fpga_bridge struct if successful.
- * Return -EBUSY if someone already has a reference to the bridge.
- * Return -ENODEV if @np is not an FPGA Bridge.
+ * Return:
+ * * fpga_bridge struct pointer if successful.
+ * * -EBUSY if someone already has a reference to the bridge.
+ * * -ENODEV if @np is not an FPGA Bridge or can't take parent driver refcount.
  */
 struct fpga_bridge *of_fpga_bridge_get(struct device_node *np,
 				       struct fpga_image_info *info)
 {
-	struct device *dev;
+	struct fpga_bridge *bridge;
+	struct device *bridge_dev;
 
-	dev = class_find_device_by_of_node(fpga_bridge_class, np);
-	if (!dev)
+	bridge_dev = class_find_device_by_of_node(&fpga_bridge_class, np);
+	if (!bridge_dev)
 		return ERR_PTR(-ENODEV);
 
-	return __fpga_bridge_get(dev, info);
+	bridge = __fpga_bridge_get(bridge_dev, info);
+	if (IS_ERR(bridge))
+		put_device(bridge_dev);
+
+	return bridge;
 }
 EXPORT_SYMBOL_GPL(of_fpga_bridge_get);
 
@@ -124,14 +123,19 @@ static int fpga_bridge_dev_match(struct device *dev, const void *data)
 struct fpga_bridge *fpga_bridge_get(struct device *dev,
 				    struct fpga_image_info *info)
 {
+	struct fpga_bridge *bridge;
 	struct device *bridge_dev;
 
-	bridge_dev = class_find_device(fpga_bridge_class, NULL, dev,
+	bridge_dev = class_find_device(&fpga_bridge_class, NULL, dev,
 				       fpga_bridge_dev_match);
 	if (!bridge_dev)
 		return ERR_PTR(-ENODEV);
 
-	return __fpga_bridge_get(bridge_dev, info);
+	bridge = __fpga_bridge_get(bridge_dev, info);
+	if (IS_ERR(bridge))
+		put_device(bridge_dev);
+
+	return bridge;
 }
 EXPORT_SYMBOL_GPL(fpga_bridge_get);
 
@@ -145,7 +149,7 @@ void fpga_bridge_put(struct fpga_bridge *bridge)
 	dev_dbg(&bridge->dev, "put\n");
 
 	bridge->info = NULL;
-	module_put(bridge->dev.parent->driver->owner);
+	module_put(bridge->br_ops_owner);
 	mutex_unlock(&bridge->mutex);
 	put_device(&bridge->dev);
 }
@@ -155,9 +159,9 @@ EXPORT_SYMBOL_GPL(fpga_bridge_put);
  * fpga_bridges_enable - enable bridges in a list
  * @bridge_list: list of FPGA bridges
  *
- * Enable each bridge in the list.  If list is empty, do nothing.
+ * Enable each bridge in the list. If list is empty, do nothing.
  *
- * Return 0 for success or empty bridge list; return error code otherwise.
+ * Return: 0 for success or empty bridge list or an error code otherwise.
  */
 int fpga_bridges_enable(struct list_head *bridge_list)
 {
@@ -179,9 +183,9 @@ EXPORT_SYMBOL_GPL(fpga_bridges_enable);
  *
  * @bridge_list: list of FPGA bridges
  *
- * Disable each bridge in the list.  If list is empty, do nothing.
+ * Disable each bridge in the list. If list is empty, do nothing.
  *
- * Return 0 for success or empty bridge list; return error code otherwise.
+ * Return: 0 for success or empty bridge list or an error code otherwise.
  */
 int fpga_bridges_disable(struct list_head *bridge_list)
 {
@@ -230,7 +234,7 @@ EXPORT_SYMBOL_GPL(fpga_bridges_put);
  *
  * Get an exclusive reference to the bridge and it to the list.
  *
- * Return 0 for success, error code from of_fpga_bridge_get() otherwise.
+ * Return: 0 for success, error code from of_fpga_bridge_get() otherwise.
  */
 int of_fpga_bridge_get_to_list(struct device_node *np,
 			       struct fpga_image_info *info,
@@ -260,7 +264,7 @@ EXPORT_SYMBOL_GPL(of_fpga_bridge_get_to_list);
  *
  * Get an exclusive reference to the bridge and it to the list.
  *
- * Return 0 for success, error code from fpga_bridge_get() otherwise.
+ * Return: 0 for success, error code from fpga_bridge_get() otherwise.
  */
 int fpga_bridge_get_to_list(struct device *dev,
 			    struct fpga_image_info *info,
@@ -295,7 +299,7 @@ static ssize_t state_show(struct device *dev,
 	struct fpga_bridge *bridge = to_fpga_bridge(dev);
 	int state = 1;
 
-	if (bridge->br_ops && bridge->br_ops->enable_show) {
+	if (bridge->br_ops->enable_show) {
 		state = bridge->br_ops->enable_show(bridge);
 		if (state < 0)
 			return state;
@@ -315,18 +319,19 @@ static struct attribute *fpga_bridge_attrs[] = {
 ATTRIBUTE_GROUPS(fpga_bridge);
 
 /**
- * fpga_bridge_register - create and register an FPGA Bridge device
+ * __fpga_bridge_register - create and register an FPGA Bridge device
  * @parent:	FPGA bridge device from pdev
  * @name:	FPGA bridge name
  * @br_ops:	pointer to structure of fpga bridge ops
  * @priv:	FPGA bridge private data
+ * @owner:	owner module containing the br_ops
  *
  * Return: struct fpga_bridge pointer or ERR_PTR()
  */
 struct fpga_bridge *
-fpga_bridge_register(struct device *parent, const char *name,
-		     const struct fpga_bridge_ops *br_ops,
-		     void *priv)
+__fpga_bridge_register(struct device *parent, const char *name,
+		       const struct fpga_bridge_ops *br_ops,
+		       void *priv, struct module *owner)
 {
 	struct fpga_bridge *bridge;
 	int id, ret;
@@ -356,10 +361,11 @@ fpga_bridge_register(struct device *parent, const char *name,
 
 	bridge->name = name;
 	bridge->br_ops = br_ops;
+	bridge->br_ops_owner = owner;
 	bridge->priv = priv;
 
 	bridge->dev.groups = br_ops->groups;
-	bridge->dev.class = fpga_bridge_class;
+	bridge->dev.class = &fpga_bridge_class;
 	bridge->dev.parent = parent;
 	bridge->dev.of_node = parent->of_node;
 	bridge->dev.id = id;
@@ -385,7 +391,7 @@ error_kfree:
 
 	return ERR_PTR(ret);
 }
-EXPORT_SYMBOL_GPL(fpga_bridge_register);
+EXPORT_SYMBOL_GPL(__fpga_bridge_register);
 
 /**
  * fpga_bridge_unregister - unregister an FPGA bridge
@@ -400,7 +406,7 @@ void fpga_bridge_unregister(struct fpga_bridge *bridge)
 	 * If the low level driver provides a method for putting bridge into
 	 * a desired state upon unregister, do it.
 	 */
-	if (bridge->br_ops && bridge->br_ops->fpga_bridge_remove)
+	if (bridge->br_ops->fpga_bridge_remove)
 		bridge->br_ops->fpga_bridge_remove(bridge);
 
 	device_unregister(&bridge->dev);
@@ -415,21 +421,20 @@ static void fpga_bridge_dev_release(struct device *dev)
 	kfree(bridge);
 }
 
+static const struct class fpga_bridge_class = {
+	.name = "fpga_bridge",
+	.dev_groups = fpga_bridge_groups,
+	.dev_release = fpga_bridge_dev_release,
+};
+
 static int __init fpga_bridge_dev_init(void)
 {
-	fpga_bridge_class = class_create("fpga_bridge");
-	if (IS_ERR(fpga_bridge_class))
-		return PTR_ERR(fpga_bridge_class);
-
-	fpga_bridge_class->dev_groups = fpga_bridge_groups;
-	fpga_bridge_class->dev_release = fpga_bridge_dev_release;
-
-	return 0;
+	return class_register(&fpga_bridge_class);
 }
 
 static void __exit fpga_bridge_dev_exit(void)
 {
-	class_destroy(fpga_bridge_class);
+	class_unregister(&fpga_bridge_class);
 	ida_destroy(&fpga_bridge_ida);
 }